C# 9 Cleanup (#325)

- [X] Removes EventArgs - not needed
- [X] Merges sequential checks
- [X] Removes redundant type declarations

Projects/Server/Events/ServerCrashedEvent.cs

@@ -17,7 +17,7 @@ using System;
 
 namespace Server
 {
-    public class ServerCrashedEventArgs : EventArgs
+    public class ServerCrashedEventArgs
     {
         public ServerCrashedEventArgs(Exception e) => Exception = e;